Buttonhole machine



June 1923.

, Y 1,457,742 H. C. MILLER BUTTONHOLE MACHINE Filed Sept. 15. 1917 5Sheets-Sheet l June 5, 1923. 7 1,457,742 H. c. MILLER BUTTONHOLE MACHINEFiled Sept. 15.1917 1 5 Sheets-Sheef 2 v 61 61. g q QMQ .n \NN"\ June 5,1923.

HPC. MILLER BUTTQNHOLE MACHINE Filed Sept. 15. 1917 5 Sheets-Sheet 5June 5, 1923. 1,457,742

H. C. MILLER BUTTONHOLE MACHINE Filed Sept. 15. 1917 5 Sheets-Sheet 4 .1r 3 r 2,1 I

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June'5, 1923. 1,457,742

. H. C. MILLER BUTTONHOLE MACHINE Filed Sept. 15. 1917 5 Sheets-Sheet 53n0e1o Patented June 5, 1923,.

N TE 's'r HENRY C. MILLER, 01? WATERFORD, NEW YORK.

BfiT'J-ONHOLE MACHINE.

To all whom it may concern:

Be it known that I, HENRY C. MILLER, a citizen of the United States ofAmerica, residing at WVaterford, in the county of Saratoga and State ofNew York, have invented certain new and useful Improvements inButtonhole Machines, of which the following is a specification.

This invention relates to improvements in buttonhole machines, and moreparticularly to the means for supplying the needle thread more freelyfrom the supply than is possible with present machines, and safety meansfor protecting the delicate mechanism against damage when the machine isnot operating properly.

With present buttonhole machines the needle thread, which is oftendefective, is drawn thru the tension devices from the supply which isnot always as free as it should be, with the result that the threadfrequently breaks, and results in the production of damaged work. Whenthe operator lifts the work clamp and removes the collar, it isdifiicult, and in many instances, impossible, to again gage the collarand repair the buttonhole stitches with any degree of satisfaction. Oneof the objects of this invention is to provide means for pullingsuflicient thread from the supply at the time of release of the tensionto form the barring stitches, to form the purl stitches, which relievesthe strain on the thread and affords a degree of safety against damagedwork.

A further object of the'invention is to provide mechanism controlled by,the tension of the needle thread for preventing the raising of the workclamp if the thread should break, or become unsually slack, or in caseof loose or skipped stitches, which will prevent the operator raisin theclamp. By this means the usual cycle of operation of forming abuttonhole can be performed, but the work clamp cannot be ,lifted whichserves as. a warning to the operator that something is wrong. If thethread is broken the needle is rethreaded, or if the stitches haveskipped, the proper. adjustments are made, or the tension is regulated,then the buttonhole is restitched without having removed the collar fromunder the clamp.

Another object of this invention is to provide safety means forpreventing damage to the cutter blade and associated parts, if for anreason the blade sticks, or the stop mechamsm .fails to stop at thepredetermined point of rest. With this means the operator is preventedfrom starting'the mecha-- nism until the cutting blade or other elementshave assumed normal position.

Primarily the object of the invention is to provide mechanism forpreventing inexperienced or careless operators damaging the parts, andat the same time preclude the possibility of removing a collar frombelow the work clamp when the needle or bobbin thread runs out orbreaks, which will subsequently allow the o erator to mend thebuttonhole, or restitc the edges thereof while the collar is in gagedand clamped position.

The invention also comprehends improvements in the detailsofconstruction and arrangement of parts which will be hereinafterdescribed and particularly pointed out in the claims.

In the accompanying drawings Figure 1 is a perspective view of a Singerbuttonhole machine, illustrating the application of my invention.

Fig. 2 is a side elevation of the same.

Fig. 3 is a conventional horizontal section Serial No. 214,654, filed.Jan. 31, 1918, I

have illustrated a loader and de icted conventionally the .buttonholemacliine about to be described. In the application referred to it may bereadily seen how the various elements in the present case are ofpractical and commercial I advantage, but it is not deemed necessaryhere to show and describe the general application of the invention, asthe subjct matter relates to improvements in the button hole' mechanismper se.

The numeral 1 indicates a base, supporting a head 2, on which is mounteda needle bar 3, tension device 4, stop mechanism 5, fast and loosepulleys 6 6*, and a work clamp 7 and below the base of the machine is ,abobbin to cooperate with the needle in the stitching operation. Rotatingwith the fast pulley is a cam .8, provided with a notch 9,

in. which a spring locating pin 10 engages when the parts are at rest.The pin 10, slides in a frame 11, pivoted at 13, and from the upper endof this frame extends an arm 12, carrying a belt guide 13. Projectingfrom the opposite side of the frame 11, is an arm 13, and pivotedthereto is a rod 14, which projects through an opening in the base andis connected to the automatic timing mechanism (not shown) to actuatethe parts after a predetermined cycle of operation has been completed.

Located on one side the head is a shaft 16, provided on one end with alever 17 which is normally pulled down by a spring 17*, and whichcarries a sprin actuated pin 18, which engages the flange edge of amember 19, attachedto the pin 10. On the opposite end of this shaft issecured an arm 18, which releases the upper thread trimming mechanism 19Loosely mounted on the shaft is a lever 20, provided on one edge with acam 21. This lever extends through a slot in the base and engages theslotted end of a lever 22. The opposite end of the lever 22 engages apin 22 on a slide 22", which carries a lower thread trimming blade 22.

All the above mentioned parts are old in the art are but conventionallyshown for the purpose of illustrating the application of my invention.

Mounted-in bearings 26, on the base, is a transverse shaft 27, on oneend of which is a handle 28, and on the opposite end is a lever 29,extending in opposite directions from the shaft. On the shaft 27,adjacent the lever 29, is a bifurcated arm 30, and in the bifurcated endis mounted a roller 31, which is located over the tail piece 32, of thework clamp 7. Extending laterally from the arm 30, are cars betweenwhich is mounted a roller 33, disposed to act on the cam 21, on thelever 20, when the shaft 27' is rocked. Fixedly secured to a lug 34, onthe arm 30, is a latch lever 34*, the free end of which is disposed tobe in the path of the nose 35, of a stop or catch 36, secured to theshaft 16.

Pivoted to the side of the head 2, at 37, is a lever 38, one end ofwhich is formed with an opening 39, and through this opening extends arod 40, pivoted at'its lower end to the latch lever 34. On the rod 40,is adjustably secured a collar 41, the end of the lever being drawn intocontact with the collar by' a spring 42. The opposite end of the lever38, is beveled and is guided in a bracket 43, fastened to the side ofthe head. Cooperating with the beveled end of the lever 38, is a trip44, formed with an abutment 45, designed to be brought into the path ofthe end of the lever 38, in the operation of the machine, as will appearlater on. The trip 44, is pivoted at 46, to the bracket 43, andextending from the pivot is a wire 47, bent at right angles, at 48, andthen bent outwardly, to form a controlling device which is located inthe path of the needle thread a, at a point near the needle. A spring49, is connected to a pin extending from the lower end of the trip andis connected at its upper end to the bracket 43, which tends to rocksaid trip to position the abutment in the path of the end of the lever38, when the thread breaks or becomes slack.

Mounted on a vertical pivot 51, is a latch lever 52, the free end ofwhich is normally disposed out of the path of movement of a lug or screw53, extending from the upper end of the arm 12, of the stop motiondevice, as shown in Figure 1. Secured on the lever 17, is a trip 54, theupper end of which lies behind a lug on the latch lever 52, a spring 55,attached to said latch lever serving to holdsame in contact with thetrip.

Secured to the shaft 27, is a finger 56,

which lies in the path of a lug 57, fastened to the rod 14, to rock theframe 11, to start the stitching mechanism.

In the top of the head of the usual Singer buttonhole machine ismechanism for automatically controlling the lateral throw of the needlebar, and the thread at or about the time of making theend barringstitches, such for instance as that shown in Patent No. 806231,dated'Dec. 5/05, and I utilize this mechanism to actuate a threadpull-off device to supply sufficient thread to properly form the purlstitches with as little tension or drag on the thread as possible. Asthe details of the barring mechanism are old in the art, I have notdeemed it necessary to specifically show the parts, except tlfipsedirectly employed to operate the pull- 0 60, indicates a lever pivotedat 61, to the top of the arm of the head, one end of said lever being inthe path of a lug 62, which is actuated twice during the formation of abutton-hole, when causing the formation of the barring stitches at eachend. The lever 60, and the lug 62, form part of the automatic mechanismshown in the patent above mentioned. The opposite end of lever 60, isprovided with a lug 63, which engages the edgeof a thread pull-off lever64, pivoted on the post 65, which carries the usual tension disks 66.The outer end of the pulloff lever is provided with an eye 67, and tothe opposite end is attached one end of a spring 68, to normally pullthe lever into contact with the lug 63. Adjacent the end of the lever64, is a vertical plate 70, the sides of which taper upwardly and itstop is rounded and bent over and is formed at its upper end with athread opening 71. The bottom of the plate 70, is bent to form a basewhich is formed with a slot 72, and

thru same extends a stud 73. Supported on the stud 73 is a thread checkdevice 74, and adjacent same is a thread opening 75, formed in the plate70.

The needle thread a, comes from the supply, and is passed thru theopening 71, then around the tension device 74, thence thru the opening75, to and thru the eye 67 in the pull-off lever 64. From this eye thethread is passed thru a guide 76, extending from the plate 70, andthence passes thru one of a pair of eyes 77, supported on the top of thehead, around the tension disks 66, thru the other of the eyes 77 to theend of the machine. The thread is then passed around the tension device4, to the take-up lever, and is then passed over asuitable guide, overthe controller wire 48 to and thru the needle.

In operation, the operator, thru suitable connections not shown,'rocksthe shaft 27, by pulling on the upper end of the lever 29, whichmovement causes roller 33 to contact with the cam 21 which rocks thelever 20, and thru the connections trims the. lower thread. In themovement of the lever 29, the roller 31, engages the tail piece of thework clamp, and the latter is raised to place the work in position. Thecloth having been inserted under the work clamp, the lever 29 isreleased and the usual spring 81, acts to lower the clamp and, hold thecloth in place. The operator now pulls a connection (not shown) attachedto the lower end ofthe lever 29, which rocks the shaft 27 in theopposite direction, and the finger 56 depresses the lug 57, which thruthe connection 13", rocks the frame 11 on the pivots 13, to shiftthebelt to the fast pulley 6, which starts the mechanism. This movementdisengages the'spring' actuated pin 18 from the flange 19, and thespring 17, pulling on the lever 17, rocks the shaft 16. This movement ofthe lever 17, also moves the trip 54, from behind the arm 52, and thespring pulls said arm inwardly where it will be ready to slip in thepath of movement of the lug 53, if the pin 10 fails to properly seat inthe notch 9, to cause the stop motion to assume its normal position.

It may here be stated that where the expression normal position is usedin the description and claims, it is intended to mean that the stopmotion parts are in their initial position and that the pin 10 isaccurately seated in the notch 9. Simultaneously with this movement theshaft 16 .positions the nose 35, of the catch or sto 36, in the upwardpath of movement 0 the latch lever 34. If the needle thread is properlytensioned over the controller wire 48,, it will hold the trip 44 inposition to f permit the beveled end of the lever38 to pass the'abutment 45, and assuming the parts operate In their properpredetermined 38, which sequence, the locating of the latch lever 52 inthe ath of the lug 53, and the lever 34, in t e path of the nose 35 ofthe collar, is an immaterial factor, as the parts are so timed andarranged as to permit them to be returned to normal position.

During the operation of makin a buttonhole, the clamp 7, and theassociated parts move to the left in Figure 1, which permits the springactuated finger 18", on the lever 18 to dro in the path of movement ofthe rod 19*. hen the clamp moves to the right the finger 18", forms anabutment for the rod 19 which causes the crank connection 13 to turn theupper thread trimming blade 18 in position to subsequently sever thethread. When the clamp movesto the right, and the rod 19 is held by theabutment the spring 18 is placed under tension to return the rod and thetrimming blade to initial position. Upon operation of the shaft 16, by

the stop motion, when the stitching opera- 7 6 tion is completed, thearm 18 is of course thrown upwardly which removes the lever 18" from theend of the rod 19, and the spring 18 immediately acts to throw the rodtoward the right which actuates the trimming blade to sever the needlethread. As-

sume that the buttonhole has been properly formed and the automaticmechanism has returned the parts to normal position, and the machinestops. The operator now pulls the upper end of the lever .29, and rocksthe shaft 27, and the roller 33 operating on cam 21, actuates thelowerthread trimming mechoperation of manually lifting the work clamp,the collar 41, engages the lever 38,

"and forces its free beveled end down past the abutment of the trip 44,which at this time is held against the tension of the spring 49, by thetension of the needle thread.

Now let it' beassumed that the needle thread breaks, or becomes undulyslack, or the bobbin thread runs out or stitches have been skipped.Either of these conditions will remove the pressure of the thread on thecontroller wire 48, and the spring'49,

promptly tends to move the trip toward the end of the lever 38. Itfollows then that ifthe operator has not observed the condition of thethread he will be warned that something is wrong, '-for immediately theupper end of the lever 29 is ulled to actuate the clamp it-will be foun"impossible to raise said clamp, owing to the. fact that the abutment 45'is'positioned under the lend'of lever. forms a lock, as shown in fulllines &

in Fig. 2. This locking action prevents the link 40 and its collar 41moving upwardly. Obviously, this prevents the shaft 27 being rocked, andtherefore the work. clamp cannot be elevated. The operator now rethreadsthe needle, or takes up the slack, as the case may be, and as the workis still clamped, the incomplete or damaged buttonhole is restitched inits original gaged position, thereby savingthe expense of replacementand insuring of a perfect buttonhole.

It frequently happens that the cutting blade 90, which is usuallycontrolled and operated by direct connections between the stop motiondevice and said cutting blade, for instance as shown in thepatent toAllen No. 743213 November 3,1903, sticks in the cloth, or thru lack ofpower the cam does not stop exactly in the position to permit of the pin10 engaging in the notch 9. Then this happens, and the lower trimmer isoperated, or the machine is restarted, it invariably results in damagingthe cutting blade and the delicate mechanism associated therewith. It isto prevent this occurring that I have provided the latches 36 and 52,one of which 52, prevents starting the mechanism, and the other 36,prevents the clamp being raised.

When the usual automatic mechanism (not shown) operated the stop motionand rocked the frame 11 toward normal position to bring the pin 10 inthe path of the notch, the trip 54, being free of the latch 52 and thelatter being under the influence of the spring 55, quickly positionsitself behind the lug 53, as shown in Fig. 7. Now if the notch 9 for anyreason fails to be properly positioned to receive the pin 10, thelatter-rides on the periphery of the cam, consequently the member 19cannot return the lever 17 to its nor mal position, therefore the nose35 of the catch 36, remains in the path of movement of the latch 34, asshown in dotted lines in Fig. 6, and prevents upward movement of thelatch.

lVhen. this condition occurs, and is not noticed by the operator, and ifthe latter starts to raise the clamp or start the mechanism, it followsthat neitheFoperation can be performed until the parts are manuallymoved to their correct normal position. When the machine is turned byhand to normal position, the lever 17 is rocked, which also rocks theshaft 16, and in turn the trip 54 acts to move the latch 52 out of thepath of the lug 53.

It'may be stated that the cutting blade cannot assume its normalposition until the pin 10, finally seats in the notch 9 in the cam, andas the trimmer blades 22 and 18 swing in the path of the cutting blade,it is of the utmost importance that the parts be so arranged as toinsure of the cutting blade being elevated clear of the path of movementof the trimmers before the latter can be operated to avoid bending orbreaking of the parts of the machine, or the needle. The details of thisinvention successfully meet these conditions, and positively insureagainst starting of the mechanism, or lifting the clamp if the parts donot come back to normal position.

Of course, after the pin is positioned in its notch, the catch 36 isremoved from the latch 34, and the clamp can be raised in the usual Itfollows from the foregoing description that the latches are actuated bythe stop motion when starting the mechanism, and that neither the workclamp can be elevated, nor the stitch formin mechanism started, ifperchance the cuttmg blade fails to return to normal position, or if thestop motion fails to restore the parts, after the preceding cycle ofoperation of the parts in the formation of a buttonhole is completed.The mechanism is so arranged as to prohibit the operator throwing themechanism into power unless the parts have properly completed their workand have been restored.

The mechanism is so, arranged that it preeludes the moving of the partslocked until the trouble or irregularity in the movement of the elementshas been removed.

In the formation of the buttonhole, the usual tension devices arereleased at or about the time of the formation of the end or barringstitches, and the thread has heretofore been pulled thru' all thetension devices from the usual cone or other supply. In this pullingaction, the tension devices are re leased to make the barring stitches,while the thread also for the side or purl stitches ,is pulled off whilethe tension devices are released from the thread. This eliminatesexcessive drag on the thread, which is the cause of uneven purl stitchesand breaking of thread, thereby incurring considerable delay andinconvenience in rapid operation. I have found that if suflicient threadis pulled from the source of supply when the tension devices arereleased for the formation of the end barring stitches, for making theside or purl stitches, the strain is reduced, and the needle thread isprevented from breaking, and the purl stitches are unform and in generalare greatly improved. To this end, at the time the tension devices areautomatically released to form the end barring stitches, the action ofthe parts pulls suflidevice and the supply is entirely dispensed with.This 0 eration occurs when both end barring stitc es are to be formed,consequently when starting the next succeeding buttohole there isrovided sufiicient slack thread to form the rst row of purl stitches.

In providing this means for removing the tension, it has been found tobe of considerable advantage to make the parts of such shape as topreclude the slack thread catching or binding. To this end, the plate isso shaped that if the slack thread should loop around it, the threadwill readily slip off when it is taken up. It is to accomplish thisresult that the thread guide plate is of taperin formation.

y invention also performs another function, in that if the bobbin threadruns out, or breaks, the needle thread which has been pulled cannot beworked into the cloth as there is no bobbin thread to cooperate with it.This condition immediately creates slack in the needle thread adjacentthe needle, which results in the spring 49 pulling the trip 44 into thepath of the end of the lever 38. Hence the work clamp cannot be raised,as previously described. Therefore, while the automatic means employedto prevent raising of the'clamp is normally under the control of theneedle thread, this control is such that it is equally effective topreclude the lifting of the clamp if anything unusual happens to thestitches, or the bobbin theread.

What I claim is 1. A sewingmachine having, in combination,stitch-forming mechanism including a reciprocating needle, a work-clamp,means for relatively moving the stitch-forming mechanism and work-clampto sew a group of stitches, a stop-motion device for arresting theaction of the stitch-forming mechanism with the needle out'of the workafter the stitches have been formed work-clamp opening means, a lockingelement forpreventing the opening of the work-clamp dur: ing thestitching, and means connected with said stop-motion device for shiftingsaid locking element to inefi'ective position after the machine has cometo rest.

2. A sewing machine having, in combina tion, stitch-forming mechanismincluding a reciprocatin needle, a work-clamp, means for relative ymoving the stitch-forming mechanism and work-clamp to sewa groupofstitches, a stop-motion device including a notched cam and a plungeradapted to' enter the notch in said cam to stop the machine with theneedle out of the work, a looking element for preventing the o eningsofthe work-clam during the stitc ing, and means actuate by the motion ofsaid pluner in entering said notch for shifting said inking element toinefl'ective position.

3. A sewing machine having, in combination, stitch-formi means includingan element adapted to rock said clamp-arm in a direction to release thework, a lock acting on said work-clamp openmg means independently ofsaid clamparm to prevent actuation of the latter, and means connected to:said stop-motion for'rendering said lock inefiective after the machinecomes to rest.

5. A sewing machine having, in combination, a stitch-forming mechanismincluding a reciprocating needle, a work-clamp, including an upperpivotally mounted clamparm, a stop-motion device, manually operatedmeans for rocking said clamp-arm to release the work, a lock'forpreventing manual operation of said means, and connections with saidstop-motion for rendering said lock inefiective after the machine hasbeen stopped.

6. A sewing machine having,in combination, a stitch-forming mechanismincludinga reciprocating needle, a work-holder in-' cluding an upperpivotally mounted clamparm, a stop-motion device including a notched camand a plunger adapted to enter the notch in said cam to stop themachine, manually operated means for rocking said clamp-arm to releasethe work, a lock for preventing manual operation of said means, andconnections actuated by said plunger during its motion into the notch insaid cam for rendering-said lock ineflective at the end of a stitchingperiod.

7. A sewing machine having, in combination, a-stitch-forming mechanismincluding a reciprocating needle, a work-holder including an upperpivotally mounted clamparm treadle controlled meansfor rocking saidclamp-arm to release the work, a

thread-cutter connected to said treadle-controlled means and movableacross the needle path to sever the sewing thread, a lock' forpreventing operation of said treadlecontrolled means during the sewing,and means connected to said stop-motion for rendering said lockinefiective after the needle has been lifted clear of the work on itslast ascent. a

8. Asewing machine having, in combinamechanisnr including areciprocating need 6, a main-shaft, a workclamp, a stop-motion deviceincluding a notched cam and a plunger adapted to enter the notch in saidcam to stop the machine at the completion of the last revolution of themain-shaft, a work-clamp opening device, a lock for preventing operationof the workclamp opening device during the sewing and connectionsactuated by said plunger in moving into said notch at the completion ofthe last revolution of the main-shaft for rendering said lockineffective.

9. A buttonhole machine including stitching mechanism, a work clamp,stop motion mechanism, manual means for raising the work clamp, and alatch automatically controlled by the stop motion mechanism to preventmanually lifting the work clamp should the stop motion fail to assumeits normal position when stopping the stitching mechamsm.

10. A buttonhole machine including stitching mechanism, a work clamp, acutter blade, stop motion mechanism, and a latch automaticallycontrolled by the stop motion mechanism to prevent manually lifting thework. clamp should the stop motion or the cutter blade fail to assumenormal position when stopping the stitching mechanism.

11. A buttonhole machine including a work clamp, a stop motion, manualmeans for raising the Work clamp, and automatic means to prevent manualoperation of the work clamp until the stop motion returns to normalposition.

12. A buttonhole machine including a work starting mechanism, a stop.motion, and means for preventing raising of the work clamp or operationof the starting mechanism until the stop motion is in normal positionand stops the buttonhole machine at a predetermined position.

13. A buttonhole machine including a work clamp, starting mechanism, astop motion, and latches to prevent raising the work clamp or operatingthe starting mechanism until the stop motion is in normal position.

14. A buttonhole machine, comprising stitch forming mechanism, a cuttingblade and a work clamp, and automatic means for preventing lifting thework clamp or starting the stitch forming mechanism at any time whilethe cutting blade is below its normal or elevated position.

15. A buttonhole machine comprising a cutting blade, means for operatinthe cutting blade, a thread trimming bla e, means actuated independentlyof and irrespective of the cutting blade operating means for operatingthe trimmer blade, a work clamp, .and automatic means for preventingoperation of the trimmer blade when the cutting blade is below thenormal or elevated posi tion.

16. A buttonhole machine comprising a said means being controlled by thestop motion or the tension of the thread.

17. A buttonhole machine comprising a work clamp, stop motion, a tensiondevice, a latch to preclude starting the mechanism if the stop motionstops in an abnormal position, and means to prevent the lifting of thework clamp when the thread is slack or breaks, said means beingcontrolled by the stop motion or the tension of the thread.

18. A buttonhole machine comprising a work clamp, a tension device,means for manually operating the work clamp, 21. connection with themeans for manually opera'ting the work clamp, and a trip normally thetension of the thread but adapted to move into the path of theconnection when.

the thread slacks or breaks to preclude lifting of the work clamp.

19. A buttonhole machine comprising a work clamp, a trimmer, a manuallyoperable lever for lifting the-work clamp and operating the trimmer, aconnection extending from the lever, a trip normally held out of thepath of the connection by the tension of the thread but adapted tobe-thrown into the path of said connection when the thread breaks orbecomes slack to preclude the lifting of the work clamp or the operationof the trimmer.

20. A buttonhole machine comprising stitching mechanism, a work clamp, acutting blade, a stop motion, means for operating the work clamp, meansfor preventing the lifting of the work clamp if the thread breaks orbecomes slack, and means under the control of the stop motion forpreventing the starting of the stitching mechanism if the cutting bladeis below its normal elevated position and preventing the lifting of thework clamp.

21. A buttonhole machine comprising a work clamp, a cutting blade, upperand lower thread trimming blades, one of which is operated irrespectiveof the cutting blade, and automatic means for preventing the operationof the thread trimming blades or lifting the work clamp when the cuttingvent lifting the work clamp until the stop motion is in normal position,and automatic means operated by the stop motion to control the positionof the latch.

23. A buttonhole machine comprising a work clamp, a rock shaft having anarm to raise the work clamp, a stop motion, a latch between the rockshaft and the stop motion to prevent lifting the work clamp until thestop motion is in normal position, and means connected with the rockshaft to prevent raising the work clamp if the thread breaks or becomesslack.

24. A buttonhole machine comprising a work clamp, a thread trimmer, astop motion, a connection operated by the stop motion to control theoperation of the thread trimmer, a latch, means for actuating the latchto prevent subsequent operation of the stop motion should the latter notreturn to normal position, and means on the connection for removing thelatch to its normal position when the stop motion assumes its normalposition.

25. A buttonhole machine comprising a work clamp, a thread trimmer, astop motion, a connection between the stop motion and the thread trimmerto control the operation of the latter, a trip on said connection, alocking element on said connection, a latch operated by the trip andadapted to be interposed in the path of movement of the stop motion toprevent its subsequent operation if it fails to reach its normalposition to preclude subsequent operation of the mechanism, and a latchwith which the locking element cooperates to preclude lifting of thework clamp if the stop motion fails to stop in its proper normalposition.

26. A buttonhole machine comprising stitching mechanism, a work clamp,and a cutting blade, and automatic means controlled by the tension ofthe thread to prevent lifting of" the clamp when the bobbin threadbreaks or the supply is exhausted.

27. A buttonhole machine including a work clamp, and means actuated bythe tension of the thread to prevent lifting) of the clamp when thethread breaks or ecomes slack.

28. A buttonhole machine comprising stitching mechanism including upperand lower thread trimming mechanism and a work clamp, means forautomatically operating the upper thread trimming mechanism, manualmeans for operating the lower thread trimming mechanism first andsubsequently raising the work clamp.

29. A two thread buttonhole machine comprising upper and lower threadtrimming devices, a stop motion which when operated actuates the upperthread trimming device and severs the upper thread, a cloth clamp,manual means to operate the under thread trimming mechanism and firstsever the under thread and then raise the cloth clamp.

30. A buttonhole machine comprising stitching mechanism including upperand under thread mechanism, a needle, a work clamp, and a cutting blade,and automatic means controlled by the tension of the needle thread toprevent lifting of the clamp when the under thread breaks or the supplyis exhausted.

31. A buttonhole machine comprising stitch forming mechanism, a workclamp, manual means for raising the work clamp and starting thestitching mechanism, a stop motion device, and means associated with themeans for raisin the Work clamp to prevent manual operation of said workclamp if the predetermined stitches are improperly formed.

32. A buttonhole machine comprising stitching mechanism, a work clamp,means for starting the stitching mechanism, said means being sopositioned that when the movement is reversedthe work clamp will beraised, and locking mechanism to prevent raising the work clamp if thestop motion fails to assume its normal position.

33. A buttonhole machine including a needle bar, an operating shafttherefor, a work clamp, means for manually operating the work clamp'inone direction, a stop motion, a latch controlled by the stop motion toprevent lifting of the work clamp at all times until the operating shaftis stopped at a predetermined position by the stop motion, and means onthe manual means for operating the work clamp to cooperate with thelatch to prevent manual operation of said work clamp. In testimonywhereof I aifix my signature in the presence of two witnesses.

HENRY o. MILLER.

Witnesses:

ALoNzo KNAPPEN, ELEANOR F. J ELF.

